Spraying machine drive



May 29, 1951 W. MaGPHERSON` .SPRAYING MACHINE DRN Filed Dec. 7, 1949 3"-Sheets-Sheet l May 29, 1951 w. MaGPHERsON SPRYING MACHINE DRIVE 3 Sheet's-Sheet 2 Filed Dec.l '7, 194s IN VEN TOR.

May 29, 1951 w. McPHERsoN SPRAYING MACHINE DRIVE 3 Sheets-Sheet -3 Filed Dec. 7, 1949 I NVEN TOR.

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Patented May 29, 1951 UNITED STATES PATENT OFFICE 6 Claims.

This invention relates to polishing and buffing machinery generally, and relates specifically to a reciprocable carriage for carrying a spray nozzle for spraying liquid abrasive on polishing or grinding wheels.

Prior devices for carrying spray nozzles for a bufng machine consist usually of an air cylinder, the piston rod of which is connected directly to the slide that carries the spray gun. It will readily be seen that by this method, in order to spray a 24-inch wheel it would be necessary to When the piston rod of such a cylinder is fully extended, the cylinder and piston rod would measure 48 inches. This would mean that the device would have to be built in such a manner that approximately 24 inches of it would project beyond the width of a machine in order for the spray gun to traverse the entire width of the polishing wheel. This 'arrangement would be objectionable in most plants.

An object of this invention is to provide an improved spraying attachment for spraying liquid abrasive compound or other similar material on the buffs or polishing wheels that lare used on polishing machines and similar applications.

Another object of this invention is to provide a spray nozzle carriage device for a bufng machine with all parts thereof confined to the limits of the machine.

Another object of this invention is to provide an improved flexible drive member for a spray carriage. Y

Another object of this invention is to provide an improved carriage rail having a chain guide recessed therein.

Still another object of this invention is to provide a safety link means between the carriage and chain which is automatically ejected and `disengaged by the chain guide sprocket teeth if the carriage should be inadvertently moved to the far extremes of the support rail.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawings, in which: I

Figure 1 is a general view of a known type of bufling and polishing machine, with a spray gun carriage device made in accordance with the principles of this invention;

Figure 2 is a perspective view of the carriage device illustrated on the bufiing machine in Figure 1;

Figure 3 yis a bottom view of the carriage device of Figure 2, showing some of the operating mechanism;

Figure 4 is a sectional view substantially along line 4 4 of Figure 2, for the purpose of showing the gearbox details, and therefore confusing associated mechanisms lying beyond the section line have been omitted;

Figure 5 is a detailed sectional view of the carriage upon which the spray gun nozzle is carried;

Figure 6 is an enlarged fragmentary perspective view of the particular carriage rail construction employed in the illustrated embodiment of the invention;

Figure 7 is an enlarged fragmentary view of the area of Figure 5 in which the linkage between the carriage and the drive chain takes place; and

Figure 8 is a wiring diagram of the spray control used with this improved carriage.

In Figure 1 of the drawings, a polishing machine of a known type for buing and polishing silverware is illustrated and referred to by the reference character I0. The polishing machine I0 is illustrated in its entirety for the purpose of setting forth the type of machine upon which the present invention may be very advantageously applied, and is not intended to be a limitation upon the invention in any manner. The Figure 1 illustrates one serious problem which has been overcome by the present invention. Prior to development of the present invention, devices for carrying a spray nozzle relative to the bufng wheel of the machine III were longer than the machine, and therefore premium floor space was Wasted because of the necessary spacing between machines to allow for the overhang.

In the Figure 1, the particular polishing machine I 0 is provided with a suitable buff wheel II and work holder clamp means I2. The actual operation of the machine I0 is of little importance insofar as setting forth this invention is concerned, except that it may be pointed out that the buff wheel Il must be wetted by a suitable bufng compound at regular intervals in order to properly nish the pieces held in the work holder I2. Accordingly, the improved spray nozzle carriage I3 made in accordance with the teaching of this invention is illustrated on the machine, and operates to move a spray gun I4 through a denite reciprocable path with respect to the bui wheel II. An air line I5 extends to the spray gun I4 and a line IS carries liquid buing compound. The spray gun I4 is constructed in a suitable well-known manner,

of the preferred embodiment. The spray nozzle carriage I3 is carried upon a' channel frame i1 forming a long rectangle. One longitudinal side of the frame I1 may be cosidered to be the front of the device.

is attached. The rail I8 is adapted toE carry al carriage 21, and also provides a -olose tting enclosed power track in which a ilexible drive member may be guided to power the carriage 2&1-,

Specically, in the embodiment of the inventionillustra-ted, the rail lli comprises a substantially rectangular member having a groove cut inthe faceth'ereof and having two. opposing track surfaces on the sides thereof. The rail member I8 is illustrated alone; ande in perspectivev in the Figure 6, and reference to the Figure Gf willbetter illustrate the details of construction found to be desirable for this particular embodiment.

In Figure: 6, thetrack I8 is illustrated as being provided with a longitudinal groove 2li therethrough having a mouth portion 22 opening through one face of the rail I'S. The groove 2| is also provided with an interior portion 23. The Figure 6 illustrates the enlarged natu-re of the: interior portion 23 with respect to the mouth portion 22. In Figure 7, an enlarged fragmentary portion of Figure 5 illustrates the exact shape and purpose of the preferred embodiment of the groove 2|. Figure 7 is. taken from the Figure 5, wherein a sprocket chain 24 -l is shown passing longitudinally through the groove 2l.V 'I'hesprocket chain 24 is of standard constructionA having link members connected by pins and rollers, and need not be explained at length. However, Figure '7 clearly shows that the interior portion 23 of the groove 2 I is designed to hold they chain 24 against free lateral movement, but will readily permit longitudinal movement of the chain through they groove 2 l'. Thus,

the chain 24 is closely conned and guided within the body of the rail I3, but can be readily shifted longitudinally within the interior portion 23' of the" groove 2I. The rail It is preferably made in two separate pieces as illustrated in Figures 6 and '1 for ease of manufacture, and is attached to the side of the frame I1 in any suitable manner, but the illustrated embodiment has been constructed by securing the rail I8 to the frame I1 by means of bolts 41.

In Figure 2, the left ends of the rail I8 and the frame I1 have been broken away to illustrate the location of a sprocket 26. A slot is cut through the side of the frame I1 and into the rail I8 to permit the sprocket 26 to extend out into the groove 2|. A similar sprocket 25 is mounted at the opposite end of the rail I8. The sprocket chain 24 is then threaded through the interior portion 23 of the groove 2I and engaged with the teeth of the sprockets and 26. It will readily be seen that the chain 24 can therefore be looped around behind the rail I 8 and driven in any suitable manner to cause continuous movement of the chain 24 through the groove 2 I, or preferably the chain 24 may be driven in a reciprocating manner.

To the front of the channel frame- I1, a rail member I8 of greatly improved design For the purpose of carrying the spray gun I4, it is desired to drive the chain 24 in a reciprocating manner through a predeterminable period of oscillation. In Figure 3 a drive sprocket 4I is illustrated on the bottom of the frame I1, and reference to the Figure 4 will show that the drive sprocket 4I is provided with a shaft 46 which extends upwardly into a gearbox 40. The chain 24 is passed around the drive sprocket 4I and the slack of the chain 24; is taken up by two idle sprockets 42. The idle sprockets l2 may be manually adjustable or spring actuated as desired, but in any event the chain 24 is suitably attached tothe drive sprocket 4I to drive the chain 24 around the sprockets 25 and 26 and through the groove 2| in the rail I8.

Although it is quite possible to provide other methods of causing reciprocating movement of theisprocket chain 24, the illustrated embodiment is equipped with an air cylinder 38 having a piston rod 39. Of course, there would be noadvantageinproviding a cylinder 38 with arod-i 39 long enough to produce a 1-1 drive ratio with respect tothe movement of the chainr 24, because in order to make one particular link of chain 214i move the entire length of the rail I8, if' a 1-11 drive. ratio were employed, the'total length of cylinder 3,8.' and piston. rod 39 would have to be more than double the length of the rail; I8. Accordingly, the gearbox 4I). is employed tov multiply the movement. of the piston rod 39. The gearbox 40 includes a rack 43 having suitable teeth adapted to rotatably drive a pinion 44 mounted upon shaft; 45. 'I'he pinion 44 is suitably intermeshed with a drive pinion 53. on the shaft t5 employed to drive the previously explained drive sprocket 4I. The particular embodiment illustrated has a gear ratio adapted to give four feet of chain travel for one foot of piston rod travel. However, the air cylinder 38- is of standard construction and is' suitably adjustable in its stroke whereby a movement mayv be. obtained, which when multiplied through gear box 40, will provide chain travel from four inches to 48 inches.

The rail I 8 is provided with two opposing track surfaces in the form of V tracks I9 and 20 on the edges of the rail. The carriage 21 is then provided with a top roller 28 and a bottom roller 2 Sl, asbest illustrated in Figure 5, which are formed to fit closely into the V slots of tracksv I9 and 20. The rollers 28 and 29 are mounted on the carriage 21 by means of suitable stud shafts 39. and 3|, and reference to the Figure 5 will immediately illustrate the fact that the carriage 2'1 will grip the rail I8, but is free to move longitudinally therealong. The carriage can be inserted upon the rail I8 and removed therefrom by pushing the carriage 21 beyond the end of the rail I8, but it cannot be removed by lateral pull. Of course, it is understood that other methods of mounting the carriage 21 could be resorted to without departing from the spirit and scope of this invention.

The carriage 21 is provided with a plunger 32 longitudinaly reciprocable within a slotted sleeve 33. The sleeve 33 is actually a tubular member which has been milled away to produce a shoulder 34 and a yoke 54. A suitable notch is provided in the shoulder 34, and a pin 35 passes through the plunger 32 and is adapted to engage in the notched shoulder 34. A spring 36 operates between the yoke 54 and the plunger 32 to keep the plunger 32 normally advanced to the position illustrated in Figure 5 with the pin 35 engaged in the notched shoulder 34. The plunger 32 has a reduced finger end 31 adapted to extend through the mouth portion 22 of the groove 2l and into an opening between two of the link members of the chain 24. The length of the plunger 32 and the finger portion 31 thereof is such that the finger end will not strike the back wall of the groove 2l and drag therealong, but is of suflicient length to fully engage into the chain 24 within the groove 2 I.

In the illustrated embodiment of the invention, the chain 24 is reciprocably driven through a predetermined cycle within the interior of guide rail I8. The carriage 21 is adapted to freely reciprocate upon the exterior surface of the rail I8 throughout any portion of the length of the rail I8. Therefore, the cycle and length of movement of the chain 24 within the guide'rail I8 may be set according to the length of the buff wheel II which is to be serviced by a spray of compound. Thereafter, the plunger 32 of the carriage 2li may be withdrawn by pulling the pin 35 against the urge of spring 33 and removing the engagement of the carriage 21 from the chain 24. Thereafter, the cylinder 38 may be set into operation and the carriage 21 manually 1.:

moved along the rail I8 to a position which appears to be closest to the center of the area which is to be served, and then the plunger 32 is released in order that the finger end 31 may again engage the chain 24, whereupon the carriage 21 will begin to reciprocate with the chain 24. However, if the exact position has been misjudged, the position of the carriage 21 may be readily shifted by pulling the plunger 32 and allowing several chain links to pass before rengagement l is again effected.

One particular advantage of the illustrated embodiment of the invention is that two or more carriages 21 may readily be employed at one time upon the rail I8. Therefore, if a series of different articles are to be buffed at one time, for example, it is possible to set the oscillating cycle of the chain 24 rather short and employ one carriage 21 for each of the buffmg groups.

Another particular advantage which has been discovered is that if the carriage 21 is moved too close to one end of the rail I8, and the natural movement of the chain carries the carriage 21 completely to the end of the rail I8, there will be no stalling of the drive mechanism, nor will there be any damage to the end sprockets 25 and 26 or to the carriage 21. The teeth of the sprockets 25 and 26 extend through the chain 24 in one direction, and the finger end 31 of the carriage 21 extends through the chain in the opposite dimachines, there has been illustrated an air pipe f and 49. It is usually desirable in applying bufdng compound to a buff wheel I I, to apply' the buiiing compound only in one direction of movement of the spray gun I4, and allow the spray gun I4 to return inoperative. Therefore, the solenoid valve 52 will be operated by the limit switches 48 and 49 to supply air through the line I5 only during one direction of travel, and will be inoperative in the opposite direction of travel. It is of course understood that the spray gun I4 is of a standard type to which liquid material can be supplied but will eject the liquid material only when an active air supply is provided. Therefore, control of the air supply will control the application of the liquid.

The spray gun I4 may be mounted upon the carriage 2l in any suitable manner, and is illustrated as being provided with a shaft 51 which may be inserted into a sleeve 58 on the carriage 21 and held in an operative position by means of a set screw 55.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

l. A reciprocable carriage device comprising, a rail member, a carriage mounted to ride said rail member, said rail member having a longitudinal chain groove therein, arlink chain within said groove, reciprocable power means driving said chain with a longitudinal reciprocable movement of preselected longitudinal period, guide surfaces to hold said chain within said groove for free longitudinal movement and against lateral displacement, and manually releasable selective engagement means carried by said carriage to seiectively link said carriage to said chain, whereby said carriage may be linked to said chain at any selected position along said rail member and will thereafter move through a reciprocable path corresponding to the movement of said chain.

2. A reciprocable carriage device for carrying a spray nozzle in a buimg machine comprising, a carriage rail, carriage track surfaces on said rail, flexible drive member guide surfaces recessed within said rail, said rail having a slot opening longitudinally therealong, a flexibleldrive member passing through said rail in said guide surfaces and looped behind said rail, drive means adapted to reciprocably drive said flexible drive member in said rail guide surfaces, said flexible drive member being exposed through said slot in the rail, carriage means mounted to ride on said track surfaces, and selective engagement means to extend through said slot and selectively link said carriage to said fiexible drive member, whereby said carriage may be linked to said flexible drive member at any selected position along said rail member and will thereafter move through a reciprocable path corresponding to the movement of said flexible drive member and carry a spray nozzle therealong.

3. A reciprocable carriage device comprising, a rail member having longitudinal track surfaces, said rail member having a longitudinal groove, chain guide surfaces in said groove, a link sprocket chain having open spaces therethrough, said chain guide surfaces being positioned to confine saidr sprocket chain to a longitudinal path through.l said groovel Within the body of the railmember,l sprocket, members mounted at each end of the rail member, said chain passing throughy said groove and around both said sprocket members and looping behind said rail member, said sprocket members having chain driving teeth extend-ing into said open spaces of said chain, drive means to move said chain in said groove, carriage means mounted to ride said track surfaces, a longitudinally reciprocable pin member carriedv by said carriage in position toA extend into said groove and into a selected one or. said open spaces of said chain, whereby said carriage means is moved along said rail member by said chain, and whereby the sprocket teeth push the pin member out of the chain upon movement of the carriage to the position of .me of said sprocket members.

4. A reciprocable carriage device for directing a spray nozzle along' a longitudinal builing member comprising, a carriage rail of generally rectangular cross section having front and` rear faces and side edges, said carriage rail having a longitudinal groove opening through said front face, said groove having an interior portion and a mouth portion, said interior portion being enlarged with respect to said mouth portion, a link sprocket chain having sprocket tooth openings, said interior portion of the groove being dimensioned to guide said chain longitudinally there through and prevent the chain from moving laterally through said mouth portion, said chain passing through said groove and being looped behind said rail sprocket members at the ends of said rail member to engage said sprocket openings and guide said chain in said loop, a carriage member having truck means to engage said side edges of the rai-l and guide said carriage for lon gitudinal reciprocable movement' on the rail, a longitudinally reciprocable pin member carried by said carriage in position to extend into said groove and into the sprocket openings in said link chain, said pin member being rejectable from said sprocket openings by engagement with teeth of the guide sprocket members, and chain drive means of selectable reciprocable period.

5. A reciprocable carriage comprising, a rail member having longitudinal track surfaces, said rail member having a longitudinal groove, said groove having a mouth portion and a body portion, a link chain, said main portion of the groove being dimensioned to closely conne and longitudinally guide the link chain through the groove, said chain extending through the groove and being looped behind the rail member, power means to move the chain throughv said groove, carriage means mounted to ride said track surfaces, and releasable interlocking means. to extend through said mouth portion of the groove and said carriage means to said link chain for movement of the carriage with the chain.

6. A reciprocable carriage device comprising, a rail member having a plurality of external longitudinal track surfaces, a longitudinal groove opening along said rail member, a longitudinally reciprocable power means fitted in said groove, lock surface means within said groove adapted to hold said power means against lateral movement out of said groove, a carriage to ride said rail member, said carriage having truck means to ride said track surfaces and carry said carriage. along said rail, in a position over the opening of said groove, and selective engagement means to releasably engage said carriage to said power means.

WILLIAM MACPHERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 771,877 Kuebler Oct. 11', 1904 1,045,523 Cassey Nov. 26, 1912 FOREIGN PATENTS Number Country Date 248,079 Switzerland Apr. 15, 1947 

